While the number of shares they still own has not been public since 1999, it has been estimated at around 16.6 million – 3.4 per cent of the company – which would be worth $29.6bn, or £22.5bn, according to Bloomberg.

Jeff’s brother Mark and sister Christina are also in the money: the 30,000 shares they bought for $10,000 in 1996 could now be worth around $640m (£487m).

Their parents have reportedly donated 595,027 shares to the Bezos Family Foundation, which provides education for young people, in the past. According to Bloomberg, the 25,000 they donated in 2016 were worth about $20m at the time.